*{margin: 0;padding:0; }
ul{list-style: none;}
.banner{
	max-width: 1380px;
	width: 80%;
	margin: 0 auto;
	position: relative;
	overflow: hidden;
	border-radius: 10px;
}
.banner_img{
	position: absolute;
	top: 0;
	left: 0;
}
.banner_img li {
	float: left;
}
.banner_img li img{
	width: 100%;
}
.banner_circle{
	position: absolute;
	bottom: 10px;
	width: 100%;
	text-align: center;
	font-size: 0;
}
.banner_circle li{
	width: 10px;
	height: 10px;
	background:rgba(0,0,0,0.5);
	display: block;
	border-radius: 100%;
	display: inline-block;
	margin: 0 5px;
	cursor: pointer;
}
.banner_btn{
	display: none;
}
.banner_btn span{
	display: block;
	width: 50px;
	height: 50px;/*改变高度*/
	background: rgba(0,0,0,0.6);
	color: #fff;
	font-size: 40px;
	line-height: 50px;/*随着高度改变行高*/
	text-align: center;
	cursor:pointer;
	border-radius: 25px;/*添加边框的半径*/
}
/*添加鼠标经过的样式*/
.banner_btn span:hover{
	color: red;
}
.banner_btn .banner_prev{
	position: absolute;
	left: 30px;/*改变左边的间距*/
	top: 50%;
	margin-top: -25px;/*随着高度改变进而改变顶部外边距*/
}
.banner_btn .banner_next{
	position: absolute;
	right: 30px;/*改变右边的间距*/
	top: 50%;
	margin-top: -25px;/*随着高度改变进而改变顶部外边距*/
}
.banner_circle .active{
	background-color: #f00;
}